Now we turn next to the news tonight on the bombs at the boston marathon, one week ago today. Today the city of boston paused at 2:50 p.M., The moment of the explosions, remembering the victims. And the latest thing tonight, we are told at abc news, that the surviving suspect, has begun to communicate. Abc's dan harris with that outside the hospital. Dan? Reporter: Good evening. Dzhokhar tsarnaev had his first court appearance today. He is this young man who was once a well loved member of his high school wrestling team, now officially facing a charge that could carry the death penalty. Tonight law enforcement sources tell abc news that the young man seen on this surveillance tape calmly walking through the crowd with a bomb in his bag, is now being cooperative with investigators. He has trouble speaking because of gunshot wounds to his neck, but he's communicating through writing, nodding his head, and making short vocalizations. Based on what he's told them, investigators are convinced there are no more ongoing plots. And tonight abc news has learned dzhokhar tsarnaev told investigat learned how to build a bomb on the internet. Today dzhokhar tsarnaev was officially charged with using and conspiring to use a weapon of mass struction. The complaint also contains vivid new details about the chaotic events of last thursday night when the brother tsarnaev allegedly carjacked a man. The victim describes one of the brothers getting in the car and saying, did you hear about the boston explosion? I did that. The victim says the brother then removed a magazine from his gun, displayed a bullet and said, i am serious. The victim later escaped when the brothers exited the car at this gas station in cambridge. Less than 24 hours later, dzhokhar tsarnaev was found hiding in a boat in a backyard in watertown, as seen from this police helicopter video. That white figure in the back of the boat, that's tsarnaev. Ule units, do not return fire. Reporter: Officers use a a robotic arm to tear the cover off the boat. Reporter: They then threw a soars of stun grenades. The explosion you see is the thermal camera picking up the The devices are not designed to injure, but tocracreate temporary blindness and deafness. It's one 75 decibels, but when it goes off next to you, it sounds like a volcano. Tsarnaev surrenders. Tonight 48 of the injured are still in hospitals around the city of boston. Two in critical condition. All of them expected to survive. Joke 1y0ek tsarnaev is being treated in in hospital behind me in which several of his victims are being treated.

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